The present invention relates to a technology for backing up the virtual communication channel of an asynchronous transfer mode (ATM) network by using a non-ATM line.
There has been an ATM device for communications by the use of the virtual communication channel on the ATM network, which is provided by the virtual path/virtual channel (VP/VC) fixedly set by the permanent virtual channel (PVC).
As a backup technology to deal with the failure of the virtual communication channel on the ATM device, there is known a technology that a virtual channel is set on the integrated service digital network (ISDN) line by considering the ISDN line as a transmission path for an ATM cell. This technology is specifically designed to transmit a ATM cell, which should have been transmitted using the failed virtual communication channel on the ATM network, by using the virtual channel set on the ISDN line.
According to such a backup technology, backup constitution information is set beforehand in two devices for carrying out communications by using the virtual communication channel on the ATM network. The backup constitution information contains bits of information regarding a virtual path identifier/virtual channel identifier (VPI/VCI) used to identify the VP/VC of the virtual communication channel on the ISDN line used for backing up, a band, a service class, and so on. For actual backing-up, the two devices set the virtual communication channel on the ISDN line according to the backup constitution information set therein, and then carry out communications.